* [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp @ 2022-08-11 11:58 Tom de Vries 2022-08-12 9:33 ` Luis Machado 0 siblings, 1 reply; 12+ messages in thread From: Tom de Vries @ 2022-08-11 11:58 UTC (permalink / raw) To: gdb-patches Hi, When running test-case gdb.dwarf2/dw2-dir-file-name.exp on x86_64-linux, we have: ... (gdb) break compdir_missing__ldir_missing__file_basename^M Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line 999.^M (gdb) continue^M Continuing.^M ^M Breakpoint 2, 0x00000000004004c4 in \ compdir_missing__ldir_missing__file_basename () \ at tmp-dw2-dir-file-name.c:999^M (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ compdir_missing__ldir_missing__file_basename: continue to breakpoint: \ compdir_missing__ldir_missing__file_basename ... When trying to set a breakpoint on compdir_missing__ldir_missing__file_basename, the architecture-specific prologue skipper starts at 0x4004c0 and skips past two insns, to 0x4004c4: ... 00000000004004c0 <compdir_missing__ldir_missing__file_basename>: 4004c0: 55 push %rbp 4004c1: 48 89 e5 mov %rsp,%rbp 4004c4: 8b 05 72 1b 20 00 mov 0x201b72(%rip),%eax # 60203c <v> 4004ca: 83 c0 01 add $0x1,%eax 4004cd: 89 05 69 1b 20 00 mov %eax,0x201b69(%rip) # 60203c <v> 4004d3: 90 nop 4004d4: 5d pop %rbp 4004d5: c3 ret ... And because the line table info is rudamentary: ... CU: tmp-dw2-dir-file-name.c: File name Line number Starting address View Stmt tmp-dw2-dir-file-name.c 999 0x4004c0 x tmp-dw2-dir-file-name.c 1000 0x4004d6 x tmp-dw2-dir-file-name.c - 0x4004d6 ... the address does not fall at an actual line, so the breakpoint is shown with address, both when setting it and hitting it. when running the test-case with aarch64-linux, we have similarly: ... (gdb) break compdir_missing__ldir_missing__file_basename^M Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line 999.^M ... due to the architecture-specific prologue skipper starting at 0x400610 and skipping past two insns, to 0x400618: ... 0000000000400610 <compdir_missing__ldir_missing__file_basename>: 400610: 90000100 adrp x0, 420000 <__libc_start_main@GLIBC_2.17> 400614: 9100b000 add x0, x0, #0x2c 400618: b9400000 ldr w0, [x0] 40061c: 11000401 add w1, w0, #0x1 400620: 90000100 adrp x0, 420000 <__libc_start_main@GLIBC_2.17> 400624: 9100b000 add x0, x0, #0x2c 400628: b9000001 str w1, [x0] 40062c: d503201f nop 400630: d65f03c0 ret ... But interestingly, the aarch64 architecture-specific prologue skipper is wrong. There is no prologue, and the breakpoint should be set at 0x400610. By using "break *compdir_missing__ldir_missing__file_basename" we can get the breakpoint set at 0x400610: ... (gdb) break *compdir_missing__ldir_missing__file_basename^M Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line 999.^M ... and make the test-case independent of prologue analysis. This requires us to update the expected patterns. The fix ensures that once the aarch64 architecture-specific prologue skipper will be fixed, this test-case won't start failing. Tested on x86_64-linux. Any comments? Thanks, - Tom [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp --- gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- gdb/testsuite/lib/gdb.exp | 7 ++++++- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp index 4d3f767f597..4c4c1ff07af 100644 --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp @@ -396,20 +396,20 @@ proc test { func compdir filename } { error "not absolute" } - gdb_breakpoint $func + gdb_breakpoint *$func gdb_continue_to_breakpoint $func "$func \\(\\) at .*" gdb_test_no_output "set filename-display absolute" verbose -log "expect: ${absolute}" - gdb_test "frame" " in $func \\(\\) at [string_to_regexp ${absolute}]:999" "absolute" + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp ${absolute}]:999" "absolute" gdb_test_no_output "set filename-display basename" verbose -log "expect: [file tail $filename]" - gdb_test "frame" " in $func \\(\\) at [string_to_regexp [file tail $filename]]:999" "basename" + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp [file tail $filename]]:999" "basename" gdb_test_no_output "set filename-display relative" verbose -log "expect: $filename" - gdb_test "frame" " in $func \\(\\) at [string_to_regexp $filename]:999" "relative" + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp $filename]:999" "relative" } } diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp index a8f25b5f0dd..70fc019eeb9 100644 --- a/gdb/testsuite/lib/gdb.exp +++ b/gdb/testsuite/lib/gdb.exp @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name {location_pattern .*}} { global gdb_prompt set full_name "continue to breakpoint: $name" + set re_at_in " (at|in) " + if { [regexp $re_at_in $location_pattern] } { + set re_at_in " " + } + set kfail_pattern "Process record does not support instruction 0xfae64 at.*" gdb_test_multiple "continue" $full_name { - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) $location_pattern\r\n$gdb_prompt $" { + -re "(?:Breakpoint|Temporary breakpoint) .*$re_at_in$location_pattern\r\n$gdb_prompt $" { pass $full_name } -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" { ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-11 11:58 [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp Tom de Vries @ 2022-08-12 9:33 ` Luis Machado 2022-08-15 16:01 ` Carl Love 0 siblings, 1 reply; 12+ messages in thread From: Luis Machado @ 2022-08-12 9:33 UTC (permalink / raw) To: Tom de Vries, gdb-patches On 8/11/22 12:58, Tom de Vries wrote: > Hi, > > When running test-case gdb.dwarf2/dw2-dir-file-name.exp on x86_64-linux, we > have: > ... > (gdb) break compdir_missing__ldir_missing__file_basename^M > Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line 999.^M > (gdb) continue^M > Continuing.^M > ^M > Breakpoint 2, 0x00000000004004c4 in \ > compdir_missing__ldir_missing__file_basename () \ > at tmp-dw2-dir-file-name.c:999^M > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ > compdir_missing__ldir_missing__file_basename: continue to breakpoint: \ > compdir_missing__ldir_missing__file_basename > ... > > When trying to set a breakpoint on > compdir_missing__ldir_missing__file_basename, the architecture-specific > prologue skipper starts at 0x4004c0 and skips past two insns, to 0x4004c4: > ... > 00000000004004c0 <compdir_missing__ldir_missing__file_basename>: > 4004c0: 55 push %rbp > 4004c1: 48 89 e5 mov %rsp,%rbp > 4004c4: 8b 05 72 1b 20 00 mov 0x201b72(%rip),%eax # 60203c <v> > 4004ca: 83 c0 01 add $0x1,%eax > 4004cd: 89 05 69 1b 20 00 mov %eax,0x201b69(%rip) # 60203c <v> > 4004d3: 90 nop > 4004d4: 5d pop %rbp > 4004d5: c3 ret > ... > > And because the line table info is rudamentary: > ... > CU: tmp-dw2-dir-file-name.c: > File name Line number Starting address View Stmt > tmp-dw2-dir-file-name.c 999 0x4004c0 x > tmp-dw2-dir-file-name.c 1000 0x4004d6 x > tmp-dw2-dir-file-name.c - 0x4004d6 > ... > the address does not fall at an actual line, so the breakpoint is shown with > address, both when setting it and hitting it. > > when running the test-case with aarch64-linux, we have similarly: > ... > (gdb) break compdir_missing__ldir_missing__file_basename^M > Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line 999.^M > ... > due to the architecture-specific prologue skipper starting at 0x400610 and > skipping past two insns, to 0x400618: > ... > 0000000000400610 <compdir_missing__ldir_missing__file_basename>: > 400610: 90000100 adrp x0, 420000 <__libc_start_main@GLIBC_2.17> > 400614: 9100b000 add x0, x0, #0x2c > 400618: b9400000 ldr w0, [x0] > 40061c: 11000401 add w1, w0, #0x1 > 400620: 90000100 adrp x0, 420000 <__libc_start_main@GLIBC_2.17> > 400624: 9100b000 add x0, x0, #0x2c > 400628: b9000001 str w1, [x0] > 40062c: d503201f nop > 400630: d65f03c0 ret > ... > > But interestingly, the aarch64 architecture-specific prologue skipper is > wrong. There is no prologue, and the breakpoint should be set at 0x400610. > > By using "break *compdir_missing__ldir_missing__file_basename" > we can get the breakpoint set at 0x400610: > ... > (gdb) break *compdir_missing__ldir_missing__file_basename^M > Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line 999.^M > ... > and make the test-case independent of prologue analysis. > > This requires us to update the expected patterns. > > The fix ensures that once the aarch64 architecture-specific prologue skipper > will be fixed, this test-case won't start failing. > > Tested on x86_64-linux. > > Any comments? > > Thanks, > - Tom > > [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp > > --- > gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- > gdb/testsuite/lib/gdb.exp | 7 ++++++- > 2 files changed, 10 insertions(+), 5 deletions(-) > > diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > index 4d3f767f597..4c4c1ff07af 100644 > --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > @@ -396,20 +396,20 @@ proc test { func compdir filename } { > error "not absolute" > } > > - gdb_breakpoint $func > + gdb_breakpoint *$func > gdb_continue_to_breakpoint $func "$func \\(\\) at .*" > > gdb_test_no_output "set filename-display absolute" > verbose -log "expect: ${absolute}" > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp ${absolute}]:999" "absolute" > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp ${absolute}]:999" "absolute" > > gdb_test_no_output "set filename-display basename" > verbose -log "expect: [file tail $filename]" > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp [file tail $filename]]:999" "basename" > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp [file tail $filename]]:999" "basename" > > gdb_test_no_output "set filename-display relative" > verbose -log "expect: $filename" > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp $filename]:999" "relative" > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp $filename]:999" "relative" > } > } > > diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp > index a8f25b5f0dd..70fc019eeb9 100644 > --- a/gdb/testsuite/lib/gdb.exp > +++ b/gdb/testsuite/lib/gdb.exp > @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name {location_pattern .*}} { > global gdb_prompt > set full_name "continue to breakpoint: $name" > > + set re_at_in " (at|in) " > + if { [regexp $re_at_in $location_pattern] } { > + set re_at_in " " > + } > + > set kfail_pattern "Process record does not support instruction 0xfae64 at.*" > gdb_test_multiple "continue" $full_name { > - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) $location_pattern\r\n$gdb_prompt $" { > + -re "(?:Breakpoint|Temporary breakpoint) .*$re_at_in$location_pattern\r\n$gdb_prompt $" { > pass $full_name > } > -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" { LGTM I agree that having a test that doesn't rely on prologue analysis is a good move. I'll track the aarch64 prologue analysis hiccup separate. ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-12 9:33 ` Luis Machado @ 2022-08-15 16:01 ` Carl Love 2022-08-15 16:54 ` Carl Love 0 siblings, 1 reply; 12+ messages in thread From: Carl Love @ 2022-08-15 16:01 UTC (permalink / raw) To: Luis Machado, Tom de Vries, gdb-patches Tom: Looks like the patch was applied last Friday. We are now seeing 129 test failures related to this commit on PowerPC. The failures are seen on Power 8, 9 and 10. Here is an initial bit of the failures: ... Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. (gdb) continue Continuing. [Inferior 1 (process 2520351) exited normally] (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: continue to breakpoint: compdir_missing__ldir_missing__file_basename (the program exited) set filename-display absolute (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: set filename-display absolute expect: /home/carll/GDB/build-current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir-file-name.d/rdir/tmp-dw2-dir-file-name.c frame No stack. (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: absolute set filename-display basename (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: set filename-display basename expect: tmp-dw2-dir-file-name.c frame No stack. (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: basename set filename-display relative (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: set filename-display relative expect: tmp-dw2-dir-file-name.c frame No stack. (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: relative set directories (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_relative: set directories break *compdir_missing__ldir_missing__file_relative Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line 999. (gdb) continue The program is not being run. etc. === gdb Summary === # of expected passes 129 # of unexpected failures 128 I have not had time yet to try and dig into the failures to figure out the cause. I will take a look at the failures to see what is going on. Anyway, just wanted to let you know what I am seeing on PowerPC. Carl On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches wrote: > On 8/11/22 12:58, Tom de Vries wrote: > > Hi, > > > > When running test-case gdb.dwarf2/dw2-dir-file-name.exp on x86_64- > > linux, we > > have: > > ... > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line 999.^M > > (gdb) continue^M > > Continuing.^M > > ^M > > Breakpoint 2, 0x00000000004004c4 in \ > > compdir_missing__ldir_missing__file_basename () \ > > at tmp-dw2-dir-file-name.c:999^M > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ > > compdir_missing__ldir_missing__file_basename: continue to > > breakpoint: \ > > compdir_missing__ldir_missing__file_basename > > ... > > > > When trying to set a breakpoint on > > compdir_missing__ldir_missing__file_basename, the architecture- > > specific > > prologue skipper starts at 0x4004c0 and skips past two insns, to > > 0x4004c4: > > ... > > 00000000004004c0 <compdir_missing__ldir_missing__file_basename>: > > 4004c0: 55 push %rbp > > 4004c1: 48 89 e5 mov %rsp,%rbp > > 4004c4: 8b 05 72 1b 20 > > 00 mov 0x201b72(%rip),%eax # 60203c <v> > > 4004ca: 83 c0 01 add $0x1,%eax > > 4004cd: 89 05 69 1b 20 > > 00 mov %eax,0x201b69(%rip) # 60203c <v> > > 4004d3: 90 nop > > 4004d4: 5d pop %rbp > > 4004d5: c3 ret > > ... > > > > And because the line table info is rudamentary: > > ... > > CU: tmp-dw2-dir-file-name.c: > > File name Line number Starting > > address View Stmt > > tmp-dw2-dir-file- > > name.c 999 0x4004c0 x > > tmp-dw2-dir-file- > > name.c 1000 0x4004d6 x > > tmp-dw2-dir-file-name.c - 0x4004d6 > > ... > > the address does not fall at an actual line, so the breakpoint is > > shown with > > address, both when setting it and hitting it. > > > > when running the test-case with aarch64-linux, we have similarly: > > ... > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line 999.^M > > ... > > due to the architecture-specific prologue skipper starting at > > 0x400610 and > > skipping past two insns, to 0x400618: > > ... > > 0000000000400610 <compdir_missing__ldir_missing__file_basename>: > > 400610: 90000100 adrp x0, 420000 < > > __libc_start_main@GLIBC_2.17> > > 400614: 9100b000 add x0, x0, #0x2c > > 400618: b9400000 ldr w0, [x0] > > 40061c: 11000401 add w1, w0, #0x1 > > 400620: 90000100 adrp x0, 420000 < > > __libc_start_main@GLIBC_2.17> > > 400624: 9100b000 add x0, x0, #0x2c > > 400628: b9000001 str w1, [x0] > > 40062c: d503201f nop > > 400630: d65f03c0 ret > > ... > > > > But interestingly, the aarch64 architecture-specific prologue > > skipper is > > wrong. There is no prologue, and the breakpoint should be set at > > 0x400610. > > > > By using "break *compdir_missing__ldir_missing__file_basename" > > we can get the breakpoint set at 0x400610: > > ... > > (gdb) break *compdir_missing__ldir_missing__file_basename^M > > Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line 999.^M > > ... > > and make the test-case independent of prologue analysis. > > > > This requires us to update the expected patterns. > > > > The fix ensures that once the aarch64 architecture-specific > > prologue skipper > > will be fixed, this test-case won't start failing. > > > > Tested on x86_64-linux. > > > > Any comments? > > > > Thanks, > > - Tom > > > > [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp > > > > --- > > gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- > > gdb/testsuite/lib/gdb.exp | 7 ++++++- > > 2 files changed, 10 insertions(+), 5 deletions(-) > > > > diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > index 4d3f767f597..4c4c1ff07af 100644 > > --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > @@ -396,20 +396,20 @@ proc test { func compdir filename } { > > error "not absolute" > > } > > > > - gdb_breakpoint $func > > + gdb_breakpoint *$func > > gdb_continue_to_breakpoint $func "$func \\(\\) at .*" > > > > gdb_test_no_output "set filename-display absolute" > > verbose -log "expect: ${absolute}" > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > ${absolute}]:999" "absolute" > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > ${absolute}]:999" "absolute" > > > > gdb_test_no_output "set filename-display basename" > > verbose -log "expect: [file tail $filename]" > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp [file > > tail $filename]]:999" "basename" > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp [file > > tail $filename]]:999" "basename" > > > > gdb_test_no_output "set filename-display relative" > > verbose -log "expect: $filename" > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > $filename]:999" "relative" > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > $filename]:999" "relative" > > } > > } > > > > diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp > > index a8f25b5f0dd..70fc019eeb9 100644 > > --- a/gdb/testsuite/lib/gdb.exp > > +++ b/gdb/testsuite/lib/gdb.exp > > @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name > > {location_pattern .*}} { > > global gdb_prompt > > set full_name "continue to breakpoint: $name" > > > > + set re_at_in " (at|in) " > > + if { [regexp $re_at_in $location_pattern] } { > > + set re_at_in " " > > + } > > + > > set kfail_pattern "Process record does not support > > instruction 0xfae64 at.*" > > gdb_test_multiple "continue" $full_name { > > - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) > > $location_pattern\r\n$gdb_prompt $" { > > + -re "(?:Breakpoint|Temporary breakpoint) > > .*$re_at_in$location_pattern\r\n$gdb_prompt $" { > > pass $full_name > > } > > -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" { > ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 16:01 ` Carl Love @ 2022-08-15 16:54 ` Carl Love 2022-08-15 19:12 ` will schmidt ` (2 more replies) 0 siblings, 3 replies; 12+ messages in thread From: Carl Love @ 2022-08-15 16:54 UTC (permalink / raw) To: Luis Machado, Tom de Vries, gdb-patches, Ulrich Weigand Tom: OK, I took a look at how the test used to work and how it is now working and I see what the issue is. PowerPC has two entry points, local and global. The test used to set the breakpoint for the function at the local entry point. With your changes, the breakpoint is now being set at the global breakpoint which is before the local breakpoint. The function is actually entered at the local breakpoint thus gdb never "sees" the breakpoint that was set. Specfically, here is the objdump for the test: 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: 100006e0: 02 10 40 3c lis r2,4098 <- Global entry point 100006e4: 00 7f 42 38 addi r2,r2,32512 100006e8: f8 ff e1 fb std r31,-8(r1) 100006ec: d1 ff 21 f8 stdu r1,-48(r1) 100006f0: 78 0b 3f 7c mr r31,r1 100006f4: 00 00 00 60 nop <- Local entry point 100006f8: 28 81 22 39 addi r9,r2,-32472 100006fc: 00 00 29 81 lwz r9,0(r9) 10000700: 01 00 49 39 addi r10,r9,1 10000704: 00 00 00 60 nop 10000708: 28 81 22 39 addi r9,r2,-32472 1000070c: 00 00 49 91 stw r10,0(r9) 10000710: 30 00 3f 38 addi r1,r31,48 10000714: f8 ff e1 eb ld r31,-8(r1) 10000718: 20 00 80 4e blr When I look at the output before the patch, we see: Breakpoint 2, 0x00000000100006f4 in compdir_missing__ldir_missing__file_basename () at tmp-dw2-dir-file-name.c:999 (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: continue to breakpoint: compdir_missing__ldir_missing__file_basename set filename-display absolute Note the breakpoint 2 address is 0x00000000100006f4 which is on the NOP. Instructions at addresses 0x100006e0 to 100006f0 are part of the code when the function is called via the global entry point. So previously, the breakpoint was set at local entry point. With the patch, we now see: Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. (gdb) continue Continuing. [Inferior 1 (process 2520351) exited normally] (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: continue to breakpoint: compdir_missing__ldir_missing__file_basename (the program exited) Now we note that the breakpoint 2 is set at 0x100006e0 which is the global entry point. It looks to me that we need to make sure we set the breakpoint at the local address. Off hand, I am not sure how to get your changes to "proc gdb_continue_to_breakpoint" to select the local entry point not the global entry point. Perhaps Ulrich has some ideas??? Carl Love On Mon, 2022-08-15 at 09:01 -0700, Carl Love wrote: > > Looks like the patch was applied last Friday. We are now seeing 129 > test failures related to this commit on PowerPC. The failures are > seen > on Power 8, 9 and 10. > > Here is an initial bit of the failures: > > ... > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. > (gdb) continue > Continuing. > [Inferior 1 (process 2520351) exited normally] > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: continue to breakpoint: > compdir_missing__ldir_missing__file_basename (the program exited) > set filename-display absolute > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: set filename-display > absolute > expect: /home/carll/GDB/build- > current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir- > file-name.d/rdir/tmp-dw2-dir-file-name.c > frame > No stack. > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: absolute > set filename-display basename > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: set filename-display > basename > expect: tmp-dw2-dir-file-name.c > frame > No stack. > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: basename > set filename-display relative > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: set filename-display > relative > expect: tmp-dw2-dir-file-name.c > frame > No stack. > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: relative > set directories > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_relative: set directories > break *compdir_missing__ldir_missing__file_relative > Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line > 999. > (gdb) continue > The program is not being run. > > etc. > > === gdb Summary === > > # of expected passes 129 > # of unexpected failures 128 > > I have not had time yet to try and dig into the failures to figure > out > the cause. I will take a look at the failures to see what is going > on. > > Anyway, just wanted to let you know what I am seeing on PowerPC. > > Carl > > On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches > wrote: > > On 8/11/22 12:58, Tom de Vries wrote: > > > Hi, > > > > > > When running test-case gdb.dwarf2/dw2-dir-file-name.exp on > > > x86_64- > > > linux, we > > > have: > > > ... > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line > > > 999.^M > > > (gdb) continue^M > > > Continuing.^M > > > ^M > > > Breakpoint 2, 0x00000000004004c4 in \ > > > compdir_missing__ldir_missing__file_basename () \ > > > at tmp-dw2-dir-file-name.c:999^M > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ > > > compdir_missing__ldir_missing__file_basename: continue to > > > breakpoint: \ > > > compdir_missing__ldir_missing__file_basename > > > ... > > > > > > When trying to set a breakpoint on > > > compdir_missing__ldir_missing__file_basename, the architecture- > > > specific > > > prologue skipper starts at 0x4004c0 and skips past two insns, to > > > 0x4004c4: > > > ... > > > 00000000004004c0 <compdir_missing__ldir_missing__file_basename>: > > > 4004c0: 55 push %rbp > > > 4004c1: 48 89 e5 mov %rsp,%rbp > > > 4004c4: 8b 05 72 1b 20 > > > 00 mov 0x201b72(%rip),%eax # 60203c <v> > > > 4004ca: 83 c0 01 add $0x1,%eax > > > 4004cd: 89 05 69 1b 20 > > > 00 mov %eax,0x201b69(%rip) # 60203c <v> > > > 4004d3: 90 nop > > > 4004d4: 5d pop %rbp > > > 4004d5: c3 ret > > > ... > > > > > > And because the line table info is rudamentary: > > > ... > > > CU: tmp-dw2-dir-file-name.c: > > > File name Line number Starting > > > address View Stmt > > > tmp-dw2-dir-file- > > > name.c 999 0x4004c0 x > > > tmp-dw2-dir-file- > > > name.c 1000 0x4004d6 x > > > tmp-dw2-dir-file-name.c - 0x4004d6 > > > ... > > > the address does not fall at an actual line, so the breakpoint is > > > shown with > > > address, both when setting it and hitting it. > > > > > > when running the test-case with aarch64-linux, we have similarly: > > > ... > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line > > > 999.^M > > > ... > > > due to the architecture-specific prologue skipper starting at > > > 0x400610 and > > > skipping past two insns, to 0x400618: > > > ... > > > 0000000000400610 <compdir_missing__ldir_missing__file_basename>: > > > 400610: 90000100 adrp x0, 420000 < > > > __libc_start_main@GLIBC_2.17> > > > 400614: 9100b000 add x0, x0, #0x2c > > > 400618: b9400000 ldr w0, [x0] > > > 40061c: 11000401 add w1, w0, #0x1 > > > 400620: 90000100 adrp x0, 420000 < > > > __libc_start_main@GLIBC_2.17> > > > 400624: 9100b000 add x0, x0, #0x2c > > > 400628: b9000001 str w1, [x0] > > > 40062c: d503201f nop > > > 400630: d65f03c0 ret > > > ... > > > > > > But interestingly, the aarch64 architecture-specific prologue > > > skipper is > > > wrong. There is no prologue, and the breakpoint should be set at > > > 0x400610. > > > > > > By using "break *compdir_missing__ldir_missing__file_basename" > > > we can get the breakpoint set at 0x400610: > > > ... > > > (gdb) break *compdir_missing__ldir_missing__file_basename^M > > > Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line > > > 999.^M > > > ... > > > and make the test-case independent of prologue analysis. > > > > > > This requires us to update the expected patterns. > > > > > > The fix ensures that once the aarch64 architecture-specific > > > prologue skipper > > > will be fixed, this test-case won't start failing. > > > > > > Tested on x86_64-linux. > > > > > > Any comments? > > > > > > Thanks, > > > - Tom > > > > > > [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp > > > > > > --- > > > gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- > > > gdb/testsuite/lib/gdb.exp | 7 ++++++- > > > 2 files changed, 10 insertions(+), 5 deletions(-) > > > > > > diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > index 4d3f767f597..4c4c1ff07af 100644 > > > --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > @@ -396,20 +396,20 @@ proc test { func compdir filename } { > > > error "not absolute" > > > } > > > > > > - gdb_breakpoint $func > > > + gdb_breakpoint *$func > > > gdb_continue_to_breakpoint $func "$func \\(\\) at .*" > > > > > > gdb_test_no_output "set filename-display absolute" > > > verbose -log "expect: ${absolute}" > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > ${absolute}]:999" "absolute" > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > ${absolute}]:999" "absolute" > > > > > > gdb_test_no_output "set filename-display basename" > > > verbose -log "expect: [file tail $filename]" > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp [file > > > tail $filename]]:999" "basename" > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp [file > > > tail $filename]]:999" "basename" > > > > > > gdb_test_no_output "set filename-display relative" > > > verbose -log "expect: $filename" > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > $filename]:999" "relative" > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > $filename]:999" "relative" > > > } > > > } > > > > > > diff --git a/gdb/testsuite/lib/gdb.exp > > > b/gdb/testsuite/lib/gdb.exp > > > index a8f25b5f0dd..70fc019eeb9 100644 > > > --- a/gdb/testsuite/lib/gdb.exp > > > +++ b/gdb/testsuite/lib/gdb.exp > > > @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name > > > {location_pattern .*}} { > > > global gdb_prompt > > > set full_name "continue to breakpoint: $name" > > > > > > + set re_at_in " (at|in) " <-NEED TO FIX TO ALWAYS GIVE local entry point for POWERPC ?? > > > + if { [regexp $re_at_in $location_pattern] } { > > > + set re_at_in " " > > > + } > > > + > > > set kfail_pattern "Process record does not support > > > instruction 0xfae64 at.*" > > > gdb_test_multiple "continue" $full_name { > > > - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) > > > $location_pattern\r\n$gdb_prompt $" { > > > + -re "(?:Breakpoint|Temporary breakpoint) > > > .*$re_at_in$location_pattern\r\n$gdb_prompt $" { > > > pass $full_name > > > } > > > -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" > > > { ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 16:54 ` Carl Love @ 2022-08-15 19:12 ` will schmidt 2022-08-15 19:31 ` Thiago Jung Bauermann 2022-08-16 7:43 ` Luis Machado 2022-08-17 12:01 ` Ulrich Weigand 2022-09-01 14:16 ` Tom de Vries 2 siblings, 2 replies; 12+ messages in thread From: will schmidt @ 2022-08-15 19:12 UTC (permalink / raw) To: Carl Love, Luis Machado, Tom de Vries, gdb-patches, Ulrich Weigand On Mon, 2022-08-15 at 09:54 -0700, Carl Love wrote: > Tom: > > OK, I took a look at how the test used to work and how it is now > working and I see what the issue is. > > PowerPC has two entry points, local and global. The test used to set > the breakpoint for the function at the local entry point. With your > changes, the breakpoint is now being set at the global breakpoint > which > is before the local breakpoint. The function is actually entered at > the local breakpoint thus gdb never "sees" the breakpoint that was > set. > Specfically, here is the objdump for the test: > > 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: > 100006e0: 02 10 40 > 3c lis r2,4098 <- Global entry point > 100006e4: 00 7f 42 38 addi r2,r2,32512 > 100006e8: f8 ff e1 fb std r31,-8(r1) > 100006ec: d1 ff 21 f8 stdu r1,-48(r1) > 100006f0: 78 0b 3f 7c mr r31,r1 > 100006f4: 00 00 00 > 60 nop <- Local entry point > 100006f8: 28 81 22 39 addi r9,r2,-32472 > 100006fc: 00 00 29 81 lwz r9,0(r9) > 10000700: 01 00 49 39 addi r10,r9,1 > 10000704: 00 00 00 60 nop > 10000708: 28 81 22 39 addi r9,r2,-32472 > 1000070c: 00 00 49 91 stw r10,0(r9) > 10000710: 30 00 3f 38 addi r1,r31,48 > 10000714: f8 ff e1 eb ld r31,-8(r1) > 10000718: 20 00 80 4e blr > > When I look at the output before the patch, we see: > > Breakpoint 2, 0x00000000100006f4 in > compdir_missing__ldir_missing__file_basename () at tmp-dw2-dir-file- > name.c:999 > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: continue to breakpoint: > compdir_missing__ldir_missing__file_basename > set filename-display absolute > > > Note the breakpoint 2 address is 0x00000000100006f4 which is on the > NOP. Instructions at addresses 0x100006e0 to 100006f0 are part of > the > code when the function is called via the global entry point. So > previously, the breakpoint was set at local entry point. > > With the patch, we now see: > > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line > 999. > (gdb) continue > > Continuing. > [Inferior 1 (process 2520351) exited normally] > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > compdir_missing__ldir_missing__file_basename: continue to breakpoint: > compdir_missing__ldir_missing__file_basename (the program exited) > > Now we note that the breakpoint 2 is set at 0x100006e0 which is the > global entry point. > > It looks to me that we need to make sure we set the breakpoint at the > local address. > > Off hand, I am not sure how to get your changes to "proc > gdb_continue_to_breakpoint" to select the local entry point not the > global entry point. Perhaps Ulrich has some ideas??? From a glance that the patch that updated dw2-dir-file-name.exp; ( commit cd919f5533cc8aa495acd75a6f059e5fcf2e6af9 ) the change there was effectively - gdb_breakpoint $func + gdb_breakpoint *$func with assorted regexp changes to match. The patch description goes into detail, but I interpret the gist of it as avoiding the aarch64 architecture prologue skipper, since that prologue skipper does something wrong, with entanglements in the line table info. The powerpc prologue skipper (wherever it is) was presumably handling the local/global entry points properly. Since the test now species a specific address (*$func), the prologue skipper is no longer involved. The patch should probably be reverted, but I defer to others if I've misunderstood part of this issue.. Thanks -Will > > Carl Love > > > On Mon, 2022-08-15 at 09:01 -0700, Carl Love wrote: > > > Looks like the patch was applied last Friday. We are now seeing > > 129 > > test failures related to this commit on PowerPC. The failures are > > seen > > on Power 8, 9 and 10. > > > > Here is an initial bit of the failures: > > > > ... > > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. > > (gdb) continue > > Continuing. > > [Inferior 1 (process 2520351) exited normally] > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: continue to > > breakpoint: > > compdir_missing__ldir_missing__file_basename (the program exited) > > set filename-display absolute > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: set filename-display > > absolute > > expect: /home/carll/GDB/build- > > current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir- > > file-name.d/rdir/tmp-dw2-dir-file-name.c > > frame > > No stack. > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: absolute > > set filename-display basename > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: set filename-display > > basename > > expect: tmp-dw2-dir-file-name.c > > frame > > No stack. > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: basename > > set filename-display relative > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: set filename-display > > relative > > expect: tmp-dw2-dir-file-name.c > > frame > > No stack. > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_basename: relative > > set directories > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > compdir_missing__ldir_missing__file_relative: set directories > > break *compdir_missing__ldir_missing__file_relative > > Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line > > 999. > > (gdb) continue > > The program is not being run. > > > > etc. > > > > === gdb Summary === > > > > # of expected passes 129 > > # of unexpected failures 128 > > > > I have not had time yet to try and dig into the failures to figure > > out > > the cause. I will take a look at the failures to see what is going > > on. > > > > Anyway, just wanted to let you know what I am seeing on PowerPC. > > > > Carl > > > > On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches > > wrote: > > > On 8/11/22 12:58, Tom de Vries wrote: > > > > Hi, > > > > > > > > When running test-case gdb.dwarf2/dw2-dir-file-name.exp on > > > > x86_64- > > > > linux, we > > > > have: > > > > ... > > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > > Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line > > > > 999.^M > > > > (gdb) continue^M > > > > Continuing.^M > > > > ^M > > > > Breakpoint 2, 0x00000000004004c4 in \ > > > > compdir_missing__ldir_missing__file_basename () \ > > > > at tmp-dw2-dir-file-name.c:999^M > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ > > > > compdir_missing__ldir_missing__file_basename: continue to > > > > breakpoint: \ > > > > compdir_missing__ldir_missing__file_basename > > > > ... > > > > > > > > When trying to set a breakpoint on > > > > compdir_missing__ldir_missing__file_basename, the architecture- > > > > specific > > > > prologue skipper starts at 0x4004c0 and skips past two insns, > > > > to > > > > 0x4004c4: > > > > ... > > > > 00000000004004c0 > > > > <compdir_missing__ldir_missing__file_basename>: > > > > 4004c0: 55 push %rbp > > > > 4004c1: 48 89 e5 mov %rsp,%rbp > > > > 4004c4: 8b 05 72 1b 20 > > > > 00 mov 0x201b72(%rip),%eax # 60203c <v> > > > > 4004ca: 83 c0 01 add $0x1,%eax > > > > 4004cd: 89 05 69 1b 20 > > > > 00 mov %eax,0x201b69(%rip) # 60203c <v> > > > > 4004d3: 90 nop > > > > 4004d4: 5d pop %rbp > > > > 4004d5: c3 ret > > > > ... > > > > > > > > And because the line table info is rudamentary: > > > > ... > > > > CU: tmp-dw2-dir-file-name.c: > > > > File name Line number Starting > > > > address View Stmt > > > > tmp-dw2-dir-file- > > > > name.c 999 0x4004c0 x > > > > tmp-dw2-dir-file- > > > > name.c 1000 0x4004d6 x > > > > tmp-dw2-dir-file-name.c - 0x4004d6 > > > > ... > > > > the address does not fall at an actual line, so the breakpoint > > > > is > > > > shown with > > > > address, both when setting it and hitting it. > > > > > > > > when running the test-case with aarch64-linux, we have > > > > similarly: > > > > ... > > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > > Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line > > > > 999.^M > > > > ... > > > > due to the architecture-specific prologue skipper starting at > > > > 0x400610 and > > > > skipping past two insns, to 0x400618: > > > > ... > > > > 0000000000400610 > > > > <compdir_missing__ldir_missing__file_basename>: > > > > 400610: 90000100 adrp x0, 420000 < > > > > __libc_start_main@GLIBC_2.17> > > > > 400614: 9100b000 add x0, x0, #0x2c > > > > 400618: b9400000 ldr w0, [x0] > > > > 40061c: 11000401 add w1, w0, #0x1 > > > > 400620: 90000100 adrp x0, 420000 < > > > > __libc_start_main@GLIBC_2.17> > > > > 400624: 9100b000 add x0, x0, #0x2c > > > > 400628: b9000001 str w1, [x0] > > > > 40062c: d503201f nop > > > > 400630: d65f03c0 ret > > > > ... > > > > > > > > But interestingly, the aarch64 architecture-specific prologue > > > > skipper is > > > > wrong. There is no prologue, and the breakpoint should be set > > > > at > > > > 0x400610. > > > > > > > > By using "break *compdir_missing__ldir_missing__file_basename" > > > > we can get the breakpoint set at 0x400610: > > > > ... > > > > (gdb) break *compdir_missing__ldir_missing__file_basename^M > > > > Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line > > > > 999.^M > > > > ... > > > > and make the test-case independent of prologue analysis. > > > > > > > > This requires us to update the expected patterns. > > > > > > > > The fix ensures that once the aarch64 architecture-specific > > > > prologue skipper > > > > will be fixed, this test-case won't start failing. > > > > > > > > Tested on x86_64-linux. > > > > > > > > Any comments? > > > > > > > > Thanks, > > > > - Tom > > > > > > > > [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp > > > > > > > > --- > > > > gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- > > > > gdb/testsuite/lib/gdb.exp | 7 ++++++- > > > > 2 files changed, 10 insertions(+), 5 deletions(-) > > > > > > > > diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > index 4d3f767f597..4c4c1ff07af 100644 > > > > --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > @@ -396,20 +396,20 @@ proc test { func compdir filename } { > > > > error "not absolute" > > > > } > > > > > > > > - gdb_breakpoint $func > > > > + gdb_breakpoint *$func > > > > gdb_continue_to_breakpoint $func "$func \\(\\) at .*" > > > > > > > > gdb_test_no_output "set filename-display absolute" > > > > verbose -log "expect: ${absolute}" > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > ${absolute}]:999" "absolute" > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > ${absolute}]:999" "absolute" > > > > > > > > gdb_test_no_output "set filename-display basename" > > > > verbose -log "expect: [file tail $filename]" > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > [file > > > > tail $filename]]:999" "basename" > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > [file > > > > tail $filename]]:999" "basename" > > > > > > > > gdb_test_no_output "set filename-display relative" > > > > verbose -log "expect: $filename" > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > $filename]:999" "relative" > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > $filename]:999" "relative" > > > > } > > > > } > > > > > > > > diff --git a/gdb/testsuite/lib/gdb.exp > > > > b/gdb/testsuite/lib/gdb.exp > > > > index a8f25b5f0dd..70fc019eeb9 100644 > > > > --- a/gdb/testsuite/lib/gdb.exp > > > > +++ b/gdb/testsuite/lib/gdb.exp > > > > @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name > > > > {location_pattern .*}} { > > > > global gdb_prompt > > > > set full_name "continue to breakpoint: $name" > > > > > > > > + set re_at_in " (at|in) " <-NEED > > > > TO FIX TO ALWAYS GIVE local entry point for POWERPC > > > > ?? > > > > > > > > + if { [regexp $re_at_in $location_pattern] } { > > > > + set re_at_in " " > > > > + } > > > > + > > > > set kfail_pattern "Process record does not support > > > > instruction 0xfae64 at.*" > > > > gdb_test_multiple "continue" $full_name { > > > > - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) > > > > $location_pattern\r\n$gdb_prompt $" { > > > > + -re "(?:Breakpoint|Temporary breakpoint) > > > > .*$re_at_in$location_pattern\r\n$gdb_prompt $" { > > > > pass $full_name > > > > } > > > > -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" > > > > { ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 19:12 ` will schmidt @ 2022-08-15 19:31 ` Thiago Jung Bauermann 2022-08-15 21:33 ` will schmidt 2022-08-16 7:43 ` Luis Machado 1 sibling, 1 reply; 12+ messages in thread From: Thiago Jung Bauermann @ 2022-08-15 19:31 UTC (permalink / raw) To: will schmidt Cc: Carl Love, Luis Machado, Tom de Vries, Ulrich Weigand, gdb-patches Hello, will schmidt via Gdb-patches <gdb-patches@sourceware.org> writes: > On Mon, 2022-08-15 at 09:54 -0700, Carl Love wrote: >> Tom: >> >> OK, I took a look at how the test used to work and how it is now >> working and I see what the issue is. >> >> PowerPC has two entry points, local and global. The test used to set >> the breakpoint for the function at the local entry point. With your >> changes, the breakpoint is now being set at the global breakpoint >> which >> is before the local breakpoint. The function is actually entered at >> the local breakpoint thus gdb never "sees" the breakpoint that was >> set. [ <snip> ] >> It looks to me that we need to make sure we set the breakpoint at the >> local address. >> >> Off hand, I am not sure how to get your changes to "proc >> gdb_continue_to_breakpoint" to select the local entry point not the >> global entry point. Perhaps Ulrich has some ideas??? > > > From a glance that the patch that updated dw2-dir-file-name.exp; > ( commit cd919f5533cc8aa495acd75a6f059e5fcf2e6af9 ) > the change there was effectively > > - gdb_breakpoint $func > + gdb_breakpoint *$func > > with assorted regexp changes to match. > > The patch description goes into detail, but I interpret the gist of it > as avoiding the aarch64 architecture prologue skipper, since that > prologue skipper does something wrong, with entanglements in the line > table info. > > The powerpc prologue skipper (wherever it is) was presumably handling > the local/global entry points properly. Since the test now species a > specific address (*$func), the prologue skipper is no longer involved. > > The patch should probably be reverted, but I defer to others if I've > misunderstood part of this issue.. Is it possible to force the compiler to use the global entry point? Perhaps by calling the function via a function pointer rather than as a regular function call? That would allow preserving the change to the testcase and making it work on ppc64le. -- Thiago ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 19:31 ` Thiago Jung Bauermann @ 2022-08-15 21:33 ` will schmidt 0 siblings, 0 replies; 12+ messages in thread From: will schmidt @ 2022-08-15 21:33 UTC (permalink / raw) To: Thiago Jung Bauermann Cc: Carl Love, Luis Machado, Tom de Vries, Ulrich Weigand, gdb-patches On Mon, 2022-08-15 at 19:31 +0000, Thiago Jung Bauermann wrote: > Hello, > > will schmidt via Gdb-patches <gdb-patches@sourceware.org> writes: > > > On Mon, 2022-08-15 at 09:54 -0700, Carl Love wrote: > > > Tom: > > > > > > OK, I took a look at how the test used to work and how it is now > > > working and I see what the issue is. > > > > > > PowerPC has two entry points, local and global. The test used to > > > set > > > the breakpoint for the function at the local entry point. With > > > your > > > changes, the breakpoint is now being set at the global breakpoint > > > which > > > is before the local breakpoint. The function is actually entered > > > at > > > the local breakpoint thus gdb never "sees" the breakpoint that > > > was > > > set. > > [ <snip> ] > > > > It looks to me that we need to make sure we set the breakpoint at > > > the > > > local address. > > > > > > Off hand, I am not sure how to get your changes to "proc > > > gdb_continue_to_breakpoint" to select the local entry point not > > > the > > > global entry point. Perhaps Ulrich has some ideas??? > > > > From a glance that the patch that updated dw2-dir-file-name.exp; > > ( commit cd919f5533cc8aa495acd75a6f059e5fcf2e6af9 ) > > the change there was effectively > > > > - gdb_breakpoint $func > > + gdb_breakpoint *$func > > > > with assorted regexp changes to match. > > > > The patch description goes into detail, but I interpret the gist of > > it > > as avoiding the aarch64 architecture prologue skipper, since that > > prologue skipper does something wrong, with entanglements in the > > line > > table info. > > > > The powerpc prologue skipper (wherever it is) was presumably > > handling > > the local/global entry points properly. Since the test now species > > a > > specific address (*$func), the prologue skipper is no longer > > involved. > > > > The patch should probably be reverted, but I defer to others if > > I've > > misunderstood part of this issue.. > > Is it possible to force the compiler to use the global entry point? No. :-) > Perhaps by calling the function via a function pointer rather than as > a > regular function call? That would allow preserving the change to the > testcase and making it work on ppc64le. > ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 19:12 ` will schmidt 2022-08-15 19:31 ` Thiago Jung Bauermann @ 2022-08-16 7:43 ` Luis Machado 2022-08-16 16:00 ` will schmidt 1 sibling, 1 reply; 12+ messages in thread From: Luis Machado @ 2022-08-16 7:43 UTC (permalink / raw) To: will schmidt, Carl Love, Tom de Vries, gdb-patches, Ulrich Weigand On 8/15/22 20:12, will schmidt wrote: > On Mon, 2022-08-15 at 09:54 -0700, Carl Love wrote: >> Tom: >> >> OK, I took a look at how the test used to work and how it is now >> working and I see what the issue is. >> >> PowerPC has two entry points, local and global. The test used to set >> the breakpoint for the function at the local entry point. With your >> changes, the breakpoint is now being set at the global breakpoint >> which >> is before the local breakpoint. The function is actually entered at >> the local breakpoint thus gdb never "sees" the breakpoint that was >> set. >> Specfically, here is the objdump for the test: >> >> 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: >> 100006e0: 02 10 40 >> 3c lis r2,4098 <- Global entry point >> 100006e4: 00 7f 42 38 addi r2,r2,32512 >> 100006e8: f8 ff e1 fb std r31,-8(r1) >> 100006ec: d1 ff 21 f8 stdu r1,-48(r1) >> 100006f0: 78 0b 3f 7c mr r31,r1 >> 100006f4: 00 00 00 >> 60 nop <- Local entry point >> 100006f8: 28 81 22 39 addi r9,r2,-32472 >> 100006fc: 00 00 29 81 lwz r9,0(r9) >> 10000700: 01 00 49 39 addi r10,r9,1 >> 10000704: 00 00 00 60 nop >> 10000708: 28 81 22 39 addi r9,r2,-32472 >> 1000070c: 00 00 49 91 stw r10,0(r9) >> 10000710: 30 00 3f 38 addi r1,r31,48 >> 10000714: f8 ff e1 eb ld r31,-8(r1) >> 10000718: 20 00 80 4e blr >> >> When I look at the output before the patch, we see: >> >> Breakpoint 2, 0x00000000100006f4 in >> compdir_missing__ldir_missing__file_basename () at tmp-dw2-dir-file- >> name.c:999 >> >> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: continue to breakpoint: >> compdir_missing__ldir_missing__file_basename >> set filename-display absolute >> >> >> Note the breakpoint 2 address is 0x00000000100006f4 which is on the >> NOP. Instructions at addresses 0x100006e0 to 100006f0 are part of >> the >> code when the function is called via the global entry point. So >> previously, the breakpoint was set at local entry point. >> >> With the patch, we now see: >> >> Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line >> 999. >> (gdb) continue >> >> Continuing. >> [Inferior 1 (process 2520351) exited normally] >> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: continue to breakpoint: >> compdir_missing__ldir_missing__file_basename (the program exited) >> >> Now we note that the breakpoint 2 is set at 0x100006e0 which is the >> global entry point. >> >> It looks to me that we need to make sure we set the breakpoint at the >> local address. >> >> Off hand, I am not sure how to get your changes to "proc >> gdb_continue_to_breakpoint" to select the local entry point not the >> global entry point. Perhaps Ulrich has some ideas??? > > > From a glance that the patch that updated dw2-dir-file-name.exp; > ( commit cd919f5533cc8aa495acd75a6f059e5fcf2e6af9 ) > the change there was effectively > > - gdb_breakpoint $func > + gdb_breakpoint *$func > > with assorted regexp changes to match. > > The patch description goes into detail, but I interpret the gist of it > as avoiding the aarch64 architecture prologue skipper, since that > prologue skipper does something wrong, with entanglements in the line > table info. Though the aarch64 prologue skipper is indeed mistaken here, Tom's patch only makes the test less reliant on whatever prologue skippers do and instead just got for a breakpoint straight at the entry point. It is a void function with void return type, so no much going on. Maybe it needs to be adapted somewhat to the PowerPC case? > > The powerpc prologue skipper (wherever it is) was presumably handling > the local/global entry points properly. Since the test now species a > specific address (*$func), the prologue skipper is no longer involved. How does powerpc handle a breakpoint at a particular address? > > The patch should probably be reverted, but I defer to others if I've > misunderstood part of this issue.. > > Thanks > -Will > > > > > > > > >> >> Carl Love >> >> >> On Mon, 2022-08-15 at 09:01 -0700, Carl Love wrote: >> >>> Looks like the patch was applied last Friday. We are now seeing >>> 129 >>> test failures related to this commit on PowerPC. The failures are >>> seen >>> on Power 8, 9 and 10. >>> >>> Here is an initial bit of the failures: >>> >>> ... >>> Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. >>> (gdb) continue >>> Continuing. >>> [Inferior 1 (process 2520351) exited normally] >>> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: continue to >>> breakpoint: >>> compdir_missing__ldir_missing__file_basename (the program exited) >>> set filename-display absolute >>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: set filename-display >>> absolute >>> expect: /home/carll/GDB/build- >>> current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir- >>> file-name.d/rdir/tmp-dw2-dir-file-name.c >>> frame >>> No stack. >>> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: absolute >>> set filename-display basename >>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: set filename-display >>> basename >>> expect: tmp-dw2-dir-file-name.c >>> frame >>> No stack. >>> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: basename >>> set filename-display relative >>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: set filename-display >>> relative >>> expect: tmp-dw2-dir-file-name.c >>> frame >>> No stack. >>> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_basename: relative >>> set directories >>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >>> compdir_missing__ldir_missing__file_relative: set directories >>> break *compdir_missing__ldir_missing__file_relative >>> Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line >>> 999. >>> (gdb) continue >>> The program is not being run. >>> >>> etc. >>> >>> === gdb Summary === >>> >>> # of expected passes 129 >>> # of unexpected failures 128 >>> >>> I have not had time yet to try and dig into the failures to figure >>> out >>> the cause. I will take a look at the failures to see what is going >>> on. >>> >>> Anyway, just wanted to let you know what I am seeing on PowerPC. >>> >>> Carl >>> >>> On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches >>> wrote: >>>> On 8/11/22 12:58, Tom de Vries wrote: >>>>> Hi, >>>>> >>>>> When running test-case gdb.dwarf2/dw2-dir-file-name.exp on >>>>> x86_64- >>>>> linux, we >>>>> have: >>>>> ... >>>>> (gdb) break compdir_missing__ldir_missing__file_basename^M >>>>> Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line >>>>> 999.^M >>>>> (gdb) continue^M >>>>> Continuing.^M >>>>> ^M >>>>> Breakpoint 2, 0x00000000004004c4 in \ >>>>> compdir_missing__ldir_missing__file_basename () \ >>>>> at tmp-dw2-dir-file-name.c:999^M >>>>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ >>>>> compdir_missing__ldir_missing__file_basename: continue to >>>>> breakpoint: \ >>>>> compdir_missing__ldir_missing__file_basename >>>>> ... >>>>> >>>>> When trying to set a breakpoint on >>>>> compdir_missing__ldir_missing__file_basename, the architecture- >>>>> specific >>>>> prologue skipper starts at 0x4004c0 and skips past two insns, >>>>> to >>>>> 0x4004c4: >>>>> ... >>>>> 00000000004004c0 >>>>> <compdir_missing__ldir_missing__file_basename>: >>>>> 4004c0: 55 push %rbp >>>>> 4004c1: 48 89 e5 mov %rsp,%rbp >>>>> 4004c4: 8b 05 72 1b 20 >>>>> 00 mov 0x201b72(%rip),%eax # 60203c <v> >>>>> 4004ca: 83 c0 01 add $0x1,%eax >>>>> 4004cd: 89 05 69 1b 20 >>>>> 00 mov %eax,0x201b69(%rip) # 60203c <v> >>>>> 4004d3: 90 nop >>>>> 4004d4: 5d pop %rbp >>>>> 4004d5: c3 ret >>>>> ... >>>>> >>>>> And because the line table info is rudamentary: >>>>> ... >>>>> CU: tmp-dw2-dir-file-name.c: >>>>> File name Line number Starting >>>>> address View Stmt >>>>> tmp-dw2-dir-file- >>>>> name.c 999 0x4004c0 x >>>>> tmp-dw2-dir-file- >>>>> name.c 1000 0x4004d6 x >>>>> tmp-dw2-dir-file-name.c - 0x4004d6 >>>>> ... >>>>> the address does not fall at an actual line, so the breakpoint >>>>> is >>>>> shown with >>>>> address, both when setting it and hitting it. >>>>> >>>>> when running the test-case with aarch64-linux, we have >>>>> similarly: >>>>> ... >>>>> (gdb) break compdir_missing__ldir_missing__file_basename^M >>>>> Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line >>>>> 999.^M >>>>> ... >>>>> due to the architecture-specific prologue skipper starting at >>>>> 0x400610 and >>>>> skipping past two insns, to 0x400618: >>>>> ... >>>>> 0000000000400610 >>>>> <compdir_missing__ldir_missing__file_basename>: >>>>> 400610: 90000100 adrp x0, 420000 < >>>>> __libc_start_main@GLIBC_2.17> >>>>> 400614: 9100b000 add x0, x0, #0x2c >>>>> 400618: b9400000 ldr w0, [x0] >>>>> 40061c: 11000401 add w1, w0, #0x1 >>>>> 400620: 90000100 adrp x0, 420000 < >>>>> __libc_start_main@GLIBC_2.17> >>>>> 400624: 9100b000 add x0, x0, #0x2c >>>>> 400628: b9000001 str w1, [x0] >>>>> 40062c: d503201f nop >>>>> 400630: d65f03c0 ret >>>>> ... >>>>> >>>>> But interestingly, the aarch64 architecture-specific prologue >>>>> skipper is >>>>> wrong. There is no prologue, and the breakpoint should be set >>>>> at >>>>> 0x400610. >>>>> >>>>> By using "break *compdir_missing__ldir_missing__file_basename" >>>>> we can get the breakpoint set at 0x400610: >>>>> ... >>>>> (gdb) break *compdir_missing__ldir_missing__file_basename^M >>>>> Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line >>>>> 999.^M >>>>> ... >>>>> and make the test-case independent of prologue analysis. >>>>> >>>>> This requires us to update the expected patterns. >>>>> >>>>> The fix ensures that once the aarch64 architecture-specific >>>>> prologue skipper >>>>> will be fixed, this test-case won't start failing. >>>>> >>>>> Tested on x86_64-linux. >>>>> >>>>> Any comments? >>>>> >>>>> Thanks, >>>>> - Tom >>>>> >>>>> [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp >>>>> >>>>> --- >>>>> gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- >>>>> gdb/testsuite/lib/gdb.exp | 7 ++++++- >>>>> 2 files changed, 10 insertions(+), 5 deletions(-) >>>>> >>>>> diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>>> b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>>> index 4d3f767f597..4c4c1ff07af 100644 >>>>> --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>>> +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>>> @@ -396,20 +396,20 @@ proc test { func compdir filename } { >>>>> error "not absolute" >>>>> } >>>>> >>>>> - gdb_breakpoint $func >>>>> + gdb_breakpoint *$func >>>>> gdb_continue_to_breakpoint $func "$func \\(\\) at .*" >>>>> >>>>> gdb_test_no_output "set filename-display absolute" >>>>> verbose -log "expect: ${absolute}" >>>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp >>>>> ${absolute}]:999" "absolute" >>>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp >>>>> ${absolute}]:999" "absolute" >>>>> >>>>> gdb_test_no_output "set filename-display basename" >>>>> verbose -log "expect: [file tail $filename]" >>>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp >>>>> [file >>>>> tail $filename]]:999" "basename" >>>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp >>>>> [file >>>>> tail $filename]]:999" "basename" >>>>> >>>>> gdb_test_no_output "set filename-display relative" >>>>> verbose -log "expect: $filename" >>>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp >>>>> $filename]:999" "relative" >>>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp >>>>> $filename]:999" "relative" >>>>> } >>>>> } >>>>> >>>>> diff --git a/gdb/testsuite/lib/gdb.exp >>>>> b/gdb/testsuite/lib/gdb.exp >>>>> index a8f25b5f0dd..70fc019eeb9 100644 >>>>> --- a/gdb/testsuite/lib/gdb.exp >>>>> +++ b/gdb/testsuite/lib/gdb.exp >>>>> @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name >>>>> {location_pattern .*}} { >>>>> global gdb_prompt >>>>> set full_name "continue to breakpoint: $name" >>>>> >>>>> + set re_at_in " (at|in) " <-NEED >>>>> TO FIX TO ALWAYS GIVE local entry point for POWERPC >>>>> ?? >>>>> >>>>> + if { [regexp $re_at_in $location_pattern] } { >>>>> + set re_at_in " " >>>>> + } >>>>> + >>>>> set kfail_pattern "Process record does not support >>>>> instruction 0xfae64 at.*" >>>>> gdb_test_multiple "continue" $full_name { >>>>> - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) >>>>> $location_pattern\r\n$gdb_prompt $" { >>>>> + -re "(?:Breakpoint|Temporary breakpoint) >>>>> .*$re_at_in$location_pattern\r\n$gdb_prompt $" { >>>>> pass $full_name >>>>> } >>>>> -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" >>>>> { > ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-16 7:43 ` Luis Machado @ 2022-08-16 16:00 ` will schmidt 0 siblings, 0 replies; 12+ messages in thread From: will schmidt @ 2022-08-16 16:00 UTC (permalink / raw) To: Luis Machado, Carl Love, Tom de Vries, gdb-patches, Ulrich Weigand On Tue, 2022-08-16 at 08:43 +0100, Luis Machado wrote: > On 8/15/22 20:12, will schmidt wrote: > > On Mon, 2022-08-15 at 09:54 -0700, Carl Love wrote: > > > Tom: > > > > > > OK, I took a look at how the test used to work and how it is now > > > working and I see what the issue is. > > > > > > PowerPC has two entry points, local and global. The test used to set > > > the breakpoint for the function at the local entry point. With your > > > changes, the breakpoint is now being set at the global breakpoint > > > which > > > is before the local breakpoint. The function is actually entered at > > > the local breakpoint thus gdb never "sees" the breakpoint that was > > > set. > > > Specfically, here is the objdump for the test: > > > > > > 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: > > > 100006e0: 02 10 40 > > > 3c lis r2,4098 <- Global entry point > > > 100006e4: 00 7f 42 38 addi r2,r2,32512 > > > 100006e8: f8 ff e1 fb std r31,-8(r1) > > > 100006ec: d1 ff 21 f8 stdu r1,-48(r1) > > > 100006f0: 78 0b 3f 7c mr r31,r1 > > > 100006f4: 00 00 00 > > > 60 nop <- Local entry point > > > 100006f8: 28 81 22 39 addi r9,r2,-32472 > > > 100006fc: 00 00 29 81 lwz r9,0(r9) > > > 10000700: 01 00 49 39 addi r10,r9,1 > > > 10000704: 00 00 00 60 nop > > > 10000708: 28 81 22 39 addi r9,r2,-32472 > > > 1000070c: 00 00 49 91 stw r10,0(r9) > > > 10000710: 30 00 3f 38 addi r1,r31,48 > > > 10000714: f8 ff e1 eb ld r31,-8(r1) > > > 10000718: 20 00 80 4e blr > > > > > > When I look at the output before the patch, we see: > > > > > > Breakpoint 2, 0x00000000100006f4 in > > > compdir_missing__ldir_missing__file_basename () at tmp-dw2-dir-file- > > > name.c:999 > > > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > > compdir_missing__ldir_missing__file_basename: continue to breakpoint: > > > compdir_missing__ldir_missing__file_basename > > > set filename-display absolute > > > > > > > > > Note the breakpoint 2 address is 0x00000000100006f4 which is on the > > > NOP. Instructions at addresses 0x100006e0 to 100006f0 are part of > > > the > > > code when the function is called via the global entry point. So > > > previously, the breakpoint was set at local entry point. > > > > > > With the patch, we now see: > > > > > > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line > > > 999. > > > (gdb) continue > > > > > > Continuing. > > > [Inferior 1 (process 2520351) exited normally] > > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > > compdir_missing__ldir_missing__file_basename: continue to breakpoint: > > > compdir_missing__ldir_missing__file_basename (the program exited) > > > > > > Now we note that the breakpoint 2 is set at 0x100006e0 which is the > > > global entry point. > > > > > > It looks to me that we need to make sure we set the breakpoint at the > > > local address. > > > > > > Off hand, I am not sure how to get your changes to "proc > > > gdb_continue_to_breakpoint" to select the local entry point not the > > > global entry point. Perhaps Ulrich has some ideas??? > > > > From a glance that the patch that updated dw2-dir-file-name.exp; > > ( commit cd919f5533cc8aa495acd75a6f059e5fcf2e6af9 ) > > the change there was effectively > > > > - gdb_breakpoint $func > > + gdb_breakpoint *$func > > > > with assorted regexp changes to match. > > > > The patch description goes into detail, but I interpret the gist of it > > as avoiding the aarch64 architecture prologue skipper, since that > > prologue skipper does something wrong, with entanglements in the line > > table info. > > Though the aarch64 prologue skipper is indeed mistaken here, Tom's patch only > makes the test less reliant on whatever prologue skippers do and instead just > got for a breakpoint straight at the entry point. I don't have the code up in front of me, I'll punt to Carl to point out where things are, if necessary.. :-) For PowerPC, as described in the ELFv2 ABI, that entry point is the global entry point (GEP). We also have (and use as much as possible) a local entry point (LEP). Code to update the TOC pointer (R2) exists between the two entry points, so when a local function calls this function, the TOC set-up is skipped. This was a significant part of the new ABI. And though I was hung up on the GEP/LEP gunk, I recognize the prologue skipping code also skips therest of the, um, prologue. It is perfectly fine to set a breakpoint between the two entry points, or anywhere within the prologue, we just can't expect it to hit anything between the entry points unless we are called via the global entry point. So for instance ... Dump of assembler code for function parse_size: 0x000000000000091c <+0>: addis r2,r12,2 << GEP,*parse_size 0x0000000000000920 <+4>: addi r2,r2,30180 0x0000000000000924 <+8>: mflr r0 << LEP 0x0000000000000928 <+12>: std r0,16(r1) 0x000000000000092c <+16>: std r31,-8(r1) 0x0000000000000930 <+20>: stdu r1,-144(r1) 0x0000000000000934 <+24>: mr r31,r1 0x0000000000000938 <+28>: std r3,104(r31) << End of Prologue. 0x000000000000093c <+32>: li r9,1 << start (gdb) break parse_size Breakpoint 1 at 0x93c: file get_page_size.c, line 11. (gdb) break *parse_size Breakpoint 2 at 0x91c: file get_page_size.c, line 9. (gdb) break * 0x000000000000091c Note: breakpoint 2 also set at pc 0x91c. Breakpoint 3 at 0x91c: file get_page_size.c, line 9. Thanks, -Will > > It is a void function with void return type, so no much going on. Maybe it needs > to be adapted somewhat to the PowerPC case? > > > > The powerpc prologue skipper (wherever it is) was presumably handling > > the local/global entry points properly. Since the test now species a > > specific address (*$func), the prologue skipper is no longer involved. > > How does powerpc handle a breakpoint at a particular address? > > > The patch should probably be reverted, but I defer to others if I've > > misunderstood part of this issue.. > > > > Thanks > > -Will > > > > > > > > > > > > > > > > > > > Carl Love > > > > > > > > > On Mon, 2022-08-15 at 09:01 -0700, Carl Love wrote: > > > > > > > Looks like the patch was applied last Friday. We are now seeing > > > > 129 > > > > test failures related to this commit on PowerPC. The failures are > > > > seen > > > > on Power 8, 9 and 10. > > > > > > > > Here is an initial bit of the failures: > > > > > > > > ... > > > > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. > > > > (gdb) continue > > > > Continuing. > > > > [Inferior 1 (process 2520351) exited normally] > > > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: continue to > > > > breakpoint: > > > > compdir_missing__ldir_missing__file_basename (the program exited) > > > > set filename-display absolute > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: set filename-display > > > > absolute > > > > expect: /home/carll/GDB/build- > > > > current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir- > > > > file-name.d/rdir/tmp-dw2-dir-file-name.c > > > > frame > > > > No stack. > > > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: absolute > > > > set filename-display basename > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: set filename-display > > > > basename > > > > expect: tmp-dw2-dir-file-name.c > > > > frame > > > > No stack. > > > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: basename > > > > set filename-display relative > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: set filename-display > > > > relative > > > > expect: tmp-dw2-dir-file-name.c > > > > frame > > > > No stack. > > > > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_basename: relative > > > > set directories > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: > > > > compdir_missing__ldir_missing__file_relative: set directories > > > > break *compdir_missing__ldir_missing__file_relative > > > > Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line > > > > 999. > > > > (gdb) continue > > > > The program is not being run. > > > > > > > > etc. > > > > > > > > === gdb Summary === > > > > > > > > # of expected passes 129 > > > > # of unexpected failures 128 > > > > > > > > I have not had time yet to try and dig into the failures to figure > > > > out > > > > the cause. I will take a look at the failures to see what is going > > > > on. > > > > > > > > Anyway, just wanted to let you know what I am seeing on PowerPC. > > > > > > > > Carl > > > > > > > > On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches > > > > wrote: > > > > > On 8/11/22 12:58, Tom de Vries wrote: > > > > > > Hi, > > > > > > > > > > > > When running test-case gdb.dwarf2/dw2-dir-file-name.exp on > > > > > > x86_64- > > > > > > linux, we > > > > > > have: > > > > > > ... > > > > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > > > > Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line > > > > > > 999.^M > > > > > > (gdb) continue^M > > > > > > Continuing.^M > > > > > > ^M > > > > > > Breakpoint 2, 0x00000000004004c4 in \ > > > > > > compdir_missing__ldir_missing__file_basename () \ > > > > > > at tmp-dw2-dir-file-name.c:999^M > > > > > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ > > > > > > compdir_missing__ldir_missing__file_basename: continue to > > > > > > breakpoint: \ > > > > > > compdir_missing__ldir_missing__file_basename > > > > > > ... > > > > > > > > > > > > When trying to set a breakpoint on > > > > > > compdir_missing__ldir_missing__file_basename, the architecture- > > > > > > specific > > > > > > prologue skipper starts at 0x4004c0 and skips past two insns, > > > > > > to > > > > > > 0x4004c4: > > > > > > ... > > > > > > 00000000004004c0 > > > > > > <compdir_missing__ldir_missing__file_basename>: > > > > > > 4004c0: 55 push %rbp > > > > > > 4004c1: 48 89 e5 mov %rsp,%rbp > > > > > > 4004c4: 8b 05 72 1b 20 > > > > > > 00 mov 0x201b72(%rip),%eax # 60203c <v> > > > > > > 4004ca: 83 c0 01 add $0x1,%eax > > > > > > 4004cd: 89 05 69 1b 20 > > > > > > 00 mov %eax,0x201b69(%rip) # 60203c <v> > > > > > > 4004d3: 90 nop > > > > > > 4004d4: 5d pop %rbp > > > > > > 4004d5: c3 ret > > > > > > ... > > > > > > > > > > > > And because the line table info is rudamentary: > > > > > > ... > > > > > > CU: tmp-dw2-dir-file-name.c: > > > > > > File name Line number Starting > > > > > > address View Stmt > > > > > > tmp-dw2-dir-file- > > > > > > name.c 999 0x4004c0 x > > > > > > tmp-dw2-dir-file- > > > > > > name.c 1000 0x4004d6 x > > > > > > tmp-dw2-dir-file-name.c - 0x4004d6 > > > > > > ... > > > > > > the address does not fall at an actual line, so the breakpoint > > > > > > is > > > > > > shown with > > > > > > address, both when setting it and hitting it. > > > > > > > > > > > > when running the test-case with aarch64-linux, we have > > > > > > similarly: > > > > > > ... > > > > > > (gdb) break compdir_missing__ldir_missing__file_basename^M > > > > > > Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line > > > > > > 999.^M > > > > > > ... > > > > > > due to the architecture-specific prologue skipper starting at > > > > > > 0x400610 and > > > > > > skipping past two insns, to 0x400618: > > > > > > ... > > > > > > 0000000000400610 > > > > > > <compdir_missing__ldir_missing__file_basename>: > > > > > > 400610: 90000100 adrp x0, 420000 < > > > > > > __libc_start_main@GLIBC_2.17> > > > > > > 400614: 9100b000 add x0, x0, #0x2c > > > > > > 400618: b9400000 ldr w0, [x0] > > > > > > 40061c: 11000401 add w1, w0, #0x1 > > > > > > 400620: 90000100 adrp x0, 420000 < > > > > > > __libc_start_main@GLIBC_2.17> > > > > > > 400624: 9100b000 add x0, x0, #0x2c > > > > > > 400628: b9000001 str w1, [x0] > > > > > > 40062c: d503201f nop > > > > > > 400630: d65f03c0 ret > > > > > > ... > > > > > > > > > > > > But interestingly, the aarch64 architecture-specific prologue > > > > > > skipper is > > > > > > wrong. There is no prologue, and the breakpoint should be set > > > > > > at > > > > > > 0x400610. > > > > > > > > > > > > By using "break *compdir_missing__ldir_missing__file_basename" > > > > > > we can get the breakpoint set at 0x400610: > > > > > > ... > > > > > > (gdb) break *compdir_missing__ldir_missing__file_basename^M > > > > > > Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line > > > > > > 999.^M > > > > > > ... > > > > > > and make the test-case independent of prologue analysis. > > > > > > > > > > > > This requires us to update the expected patterns. > > > > > > > > > > > > The fix ensures that once the aarch64 architecture-specific > > > > > > prologue skipper > > > > > > will be fixed, this test-case won't start failing. > > > > > > > > > > > > Tested on x86_64-linux. > > > > > > > > > > > > Any comments? > > > > > > > > > > > > Thanks, > > > > > > - Tom > > > > > > > > > > > > [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp > > > > > > > > > > > > --- > > > > > > gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- > > > > > > gdb/testsuite/lib/gdb.exp | 7 ++++++- > > > > > > 2 files changed, 10 insertions(+), 5 deletions(-) > > > > > > > > > > > > diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > > > b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > > > index 4d3f767f597..4c4c1ff07af 100644 > > > > > > --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > > > +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp > > > > > > @@ -396,20 +396,20 @@ proc test { func compdir filename } { > > > > > > error "not absolute" > > > > > > } > > > > > > > > > > > > - gdb_breakpoint $func > > > > > > + gdb_breakpoint *$func > > > > > > gdb_continue_to_breakpoint $func "$func \\(\\) at .*" > > > > > > > > > > > > gdb_test_no_output "set filename-display absolute" > > > > > > verbose -log "expect: ${absolute}" > > > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > > > ${absolute}]:999" "absolute" > > > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > > > ${absolute}]:999" "absolute" > > > > > > > > > > > > gdb_test_no_output "set filename-display basename" > > > > > > verbose -log "expect: [file tail $filename]" > > > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > > > [file > > > > > > tail $filename]]:999" "basename" > > > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > > > [file > > > > > > tail $filename]]:999" "basename" > > > > > > > > > > > > gdb_test_no_output "set filename-display relative" > > > > > > verbose -log "expect: $filename" > > > > > > - gdb_test "frame" " in $func \\(\\) at [string_to_regexp > > > > > > $filename]:999" "relative" > > > > > > + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp > > > > > > $filename]:999" "relative" > > > > > > } > > > > > > } > > > > > > > > > > > > diff --git a/gdb/testsuite/lib/gdb.exp > > > > > > b/gdb/testsuite/lib/gdb.exp > > > > > > index a8f25b5f0dd..70fc019eeb9 100644 > > > > > > --- a/gdb/testsuite/lib/gdb.exp > > > > > > +++ b/gdb/testsuite/lib/gdb.exp > > > > > > @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name > > > > > > {location_pattern .*}} { > > > > > > global gdb_prompt > > > > > > set full_name "continue to breakpoint: $name" > > > > > > > > > > > > + set re_at_in " (at|in) " <-NEED > > > > > > TO FIX TO ALWAYS GIVE local entry point for POWERPC > > > > > > ?? > > > > > > > > > > > > + if { [regexp $re_at_in $location_pattern] } { > > > > > > + set re_at_in " " > > > > > > + } > > > > > > + > > > > > > set kfail_pattern "Process record does not support > > > > > > instruction 0xfae64 at.*" > > > > > > gdb_test_multiple "continue" $full_name { > > > > > > - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) > > > > > > $location_pattern\r\n$gdb_prompt $" { > > > > > > + -re "(?:Breakpoint|Temporary breakpoint) > > > > > > .*$re_at_in$location_pattern\r\n$gdb_prompt $" { > > > > > > pass $full_name > > > > > > } > > > > > > -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" > > > > > > { ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 16:54 ` Carl Love 2022-08-15 19:12 ` will schmidt @ 2022-08-17 12:01 ` Ulrich Weigand 2022-09-01 14:40 ` Tom de Vries 2022-09-01 14:16 ` Tom de Vries 2 siblings, 1 reply; 12+ messages in thread From: Ulrich Weigand @ 2022-08-17 12:01 UTC (permalink / raw) To: gdb-patches, luis.machado, tdevries, cel Carl Love <cel@us.ibm.com> wrote: >PowerPC has two entry points, local and global. The test used to set >the breakpoint for the function at the local entry point. With your >changes, the breakpoint is now being set at the global breakpoint which >is before the local breakpoint. The function is actually entered at >the local breakpoint thus gdb never "sees" the breakpoint that was set. >Specfically, here is the objdump for the test: >00000000100006e0 <compdir_missing__ldir_missing__file_basename>: > 100006e0: 02 10 40 3c lis r2,4098 <- >Global entry point > 100006e4: 00 7f 42 38 addi r2,r2,32512 The local enty point is actually here: > 100006e8: f8 ff e1 fb std r31,-8(r1) > 100006ec: d1 ff 21 f8 stdu r1,-48(r1) > 100006f0: 78 0b 3f 7c mr r31,r1 > 100006f4: 00 00 00 60 nop <- >Local entry point > 100006f8: 28 81 22 39 addi r9,r2,-32472 Not here. This point might be the end of the prologue, which is a separate question from the local vs. global entry point issue. >Perhaps Ulrich has some ideas??? This: + gdb_breakpoint *$func is nearly always wrong, and test cases shouldn't be using it. I know that in the past, this construct was sometimes used with an intended meaning of "set a breakpoint at the start of a function without skipping the prologue", but it does *not* actually mean that. The "*" operator tells the breakpoint logic to set a breakpoint on an absolute address. If followed by a symbol, that symbol's value is used as that absolute address. Now, on many platform, that symbol value matches the address of the first instruction of a function, so the "break *func" does more or less what's intended above. But there are other platforms where this is not true, and the relationship between the function symbol value and the address of the first executed instruction is more complex. This specifically applies to targets that implement gdbarch_deprecated_function_start_offset and/or gdbarch_skip_entrypoint. (ppc64le uses the latter.) Note that these are *independent* of prologue skipping, and on platforms where it matters, they have to be used even when avoiding prologue skipping, in order to correctly find the first instruction of a function to set a breakpoint on. "break *func" ignores this, leading to failures on such platforms. As I said initially, I think this construct should never be used in test cases (at least not in scenerios where it is intended to set a breakpoint that will actually be hit). For this specific test, if the underlying problem is a bug in some architecture's prologue parser, then ideally this bug simply should be fixed. If we need to actually avoid prologue skipping for some real underlying reason, we should use a way that still handles function start offsets and entrypoint skipping. For example, in a function with debug info including valid location lists, GDB will always avoid prologue skipping. We could also think of adding an explicit linespec modifier that would allow to explicitly set a breakpoint on the first instruction of a function without skipping prologue ... Bye, Ulrich ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-17 12:01 ` Ulrich Weigand @ 2022-09-01 14:40 ` Tom de Vries 0 siblings, 0 replies; 12+ messages in thread From: Tom de Vries @ 2022-09-01 14:40 UTC (permalink / raw) To: Ulrich Weigand, gdb-patches, luis.machado, cel On 8/17/22 14:01, Ulrich Weigand wrote: > Carl Love <cel@us.ibm.com> wrote: > >> PowerPC has two entry points, local and global. The test used to set >> the breakpoint for the function at the local entry point. With your >> changes, the breakpoint is now being set at the global breakpoint > which >> is before the local breakpoint. The function is actually entered at >> the local breakpoint thus gdb never "sees" the breakpoint that was > set. >> Specfically, here is the objdump for the test: > >> 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: >> 100006e0: 02 10 40 3c lis r2,4098 <- >> Global entry point >> 100006e4: 00 7f 42 38 addi r2,r2,32512 > The local enty point is actually here: >> 100006e8: f8 ff e1 fb std r31,-8(r1) >> 100006ec: d1 ff 21 f8 stdu r1,-48(r1) >> 100006f0: 78 0b 3f 7c mr r31,r1 >> 100006f4: 00 00 00 60 nop <- >> Local entry point >> 100006f8: 28 81 22 39 addi r9,r2,-32472 > > Not here. This point might be the end of the prologue, which is a > separate question from the local vs. global entry point issue. > >> Perhaps Ulrich has some ideas??? > > This: > + gdb_breakpoint *$func > is nearly always wrong, and test cases shouldn't be using it. > Ack, I've posted a fix that doesn't use that construct anymore. > I know that in the past, this construct was sometimes used with an > intended meaning of "set a breakpoint at the start of a function > without skipping the prologue", but it does *not* actually mean that. > > The "*" operator tells the breakpoint logic to set a breakpoint on an > absolute address. If followed by a symbol, that symbol's value is used > as that absolute address. Now, on many platform, that symbol value > matches the address of the first instruction of a function, so the > "break *func" does more or less what's intended above. > > But there are other platforms where this is not true, and the > relationship between the function symbol value and the address of the > first executed instruction is more complex. This specifically applies > to targets that implement gdbarch_deprecated_function_start_offset > and/or gdbarch_skip_entrypoint. (ppc64le uses the latter.) > I think we could add a note to the docs explaining this. > Note that these are *independent* of prologue skipping, and on > platforms where it matters, they have to be used even when avoiding > prologue skipping, in order to correctly find the first instruction of > a function to set a breakpoint on. "break *func" ignores this, > leading to failures on such platforms. > > > As I said initially, I think this construct should never be used in > test cases (at least not in scenerios where it is intended to set a > breakpoint that will actually be hit). > > For this specific test, if the underlying problem is a bug in some > architecture's prologue parser, then ideally this bug simply should be > fixed. Yes, it should, and a test-case should be added for that. In this test-case, we try to test a feature that has nothing to do with architecture-specific prologue skipping, so given that there can be problems with it on various targets, the test-case should simply skip it. Thanks, - Tom > If we need to actually avoid prologue skipping for some real > underlying reason, we should use a way that still handles function > start offsets and entrypoint skipping. For example, in a function with > debug info including valid location lists, GDB will always avoid > prologue skipping. We could also think of adding an explicit linespec > modifier that would allow to explicitly set a breakpoint on the first > instruction of a function without skipping prologue ... > > > Bye, > Ulrich > ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp 2022-08-15 16:54 ` Carl Love 2022-08-15 19:12 ` will schmidt 2022-08-17 12:01 ` Ulrich Weigand @ 2022-09-01 14:16 ` Tom de Vries 2 siblings, 0 replies; 12+ messages in thread From: Tom de Vries @ 2022-09-01 14:16 UTC (permalink / raw) To: Carl Love, Luis Machado, gdb-patches, Ulrich Weigand On 8/15/22 18:54, Carl Love via Gdb-patches wrote: > Tom: > > OK, I took a look at how the test used to work and how it is now > working and I see what the issue is. > > PowerPC has two entry points, local and global. The test used to set > the breakpoint for the function at the local entry point. With your > changes, the breakpoint is now being set at the global breakpoint which > is before the local breakpoint. The function is actually entered at > the local breakpoint thus gdb never "sees" the breakpoint that was set. > Specfically, here is the objdump for the test: > > 00000000100006e0 <compdir_missing__ldir_missing__file_basename>: > 100006e0: 02 10 40 3c lis r2,4098 <- Global entry point > 100006e4: 00 7f 42 38 addi r2,r2,32512 > 100006e8: f8 ff e1 fb std r31,-8(r1) > 100006ec: d1 ff 21 f8 stdu r1,-48(r1) > 100006f0: 78 0b 3f 7c mr r31,r1 > 100006f4: 00 00 00 60 nop <- Local entry point > 100006f8: 28 81 22 39 addi r9,r2,-32472 > 100006fc: 00 00 29 81 lwz r9,0(r9) > 10000700: 01 00 49 39 addi r10,r9,1 > 10000704: 00 00 00 60 nop > 10000708: 28 81 22 39 addi r9,r2,-32472 > 1000070c: 00 00 49 91 stw r10,0(r9) > 10000710: 30 00 3f 38 addi r1,r31,48 > 10000714: f8 ff e1 eb ld r31,-8(r1) > 10000718: 20 00 80 4e blr > > When I look at the output before the patch, we see: > > Breakpoint 2, 0x00000000100006f4 in compdir_missing__ldir_missing__file_basename () at tmp-dw2-dir-file-name.c:999 > > (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: continue to breakpoint: compdir_missing__ldir_missing__file_basename > set filename-display absolute > > > Note the breakpoint 2 address is 0x00000000100006f4 which is on the > NOP. Instructions at addresses 0x100006e0 to 100006f0 are part of the > code when the function is called via the global entry point. So > previously, the breakpoint was set at local entry point. > > With the patch, we now see: > > Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. > (gdb) continue > > Continuing. > [Inferior 1 (process 2520351) exited normally] > (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: compdir_missing__ldir_missing__file_basename: continue to breakpoint: compdir_missing__ldir_missing__file_basename (the program exited) > > Now we note that the breakpoint 2 is set at 0x100006e0 which is the > global entry point. > > It looks to me that we need to make sure we set the breakpoint at the > local address. > > Off hand, I am not sure how to get your changes to "proc > gdb_continue_to_breakpoint" to select the local entry point not the > global entry point. Perhaps Ulrich has some ideas??? > Hi Carl, thanks for reporting this, and the analysis. I've submitted a patch to fix this here ( https://sourceware.org/pipermail/gdb-patches/2022-September/191647.html ). Thanks, - Tom > Carl Love > > > On Mon, 2022-08-15 at 09:01 -0700, Carl Love wrote: > >> >> Looks like the patch was applied last Friday. We are now seeing 129 >> test failures related to this commit on PowerPC. The failures are >> seen >> on Power 8, 9 and 10. >> >> Here is an initial bit of the failures: >> >> ... >> Breakpoint 2 at 0x100006e0: file tmp-dw2-dir-file-name.c, line 999. >> (gdb) continue >> Continuing. >> [Inferior 1 (process 2520351) exited normally] >> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: continue to breakpoint: >> compdir_missing__ldir_missing__file_basename (the program exited) >> set filename-display absolute >> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: set filename-display >> absolute >> expect: /home/carll/GDB/build- >> current/gdb/testsuite/outputs/gdb.dwarf2/dw2-dir-file-name/dw2-dir- >> file-name.d/rdir/tmp-dw2-dir-file-name.c >> frame >> No stack. >> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: absolute >> set filename-display basename >> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: set filename-display >> basename >> expect: tmp-dw2-dir-file-name.c >> frame >> No stack. >> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: basename >> set filename-display relative >> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: set filename-display >> relative >> expect: tmp-dw2-dir-file-name.c >> frame >> No stack. >> (gdb) FAIL: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_basename: relative >> set directories >> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: >> compdir_missing__ldir_missing__file_relative: set directories >> break *compdir_missing__ldir_missing__file_relative >> Breakpoint 3 at 0x10000728: file fdir/tmp-dw2-dir-file-name.c, line >> 999. >> (gdb) continue >> The program is not being run. >> >> etc. >> >> === gdb Summary === >> >> # of expected passes 129 >> # of unexpected failures 128 >> >> I have not had time yet to try and dig into the failures to figure >> out >> the cause. I will take a look at the failures to see what is going >> on. >> >> Anyway, just wanted to let you know what I am seeing on PowerPC. >> >> Carl >> >> On Fri, 2022-08-12 at 10:33 +0100, Luis Machado via Gdb-patches >> wrote: >>> On 8/11/22 12:58, Tom de Vries wrote: >>>> Hi, >>>> >>>> When running test-case gdb.dwarf2/dw2-dir-file-name.exp on >>>> x86_64- >>>> linux, we >>>> have: >>>> ... >>>> (gdb) break compdir_missing__ldir_missing__file_basename^M >>>> Breakpoint 2 at 0x4004c4: file tmp-dw2-dir-file-name.c, line >>>> 999.^M >>>> (gdb) continue^M >>>> Continuing.^M >>>> ^M >>>> Breakpoint 2, 0x00000000004004c4 in \ >>>> compdir_missing__ldir_missing__file_basename () \ >>>> at tmp-dw2-dir-file-name.c:999^M >>>> (gdb) PASS: gdb.dwarf2/dw2-dir-file-name.exp: \ >>>> compdir_missing__ldir_missing__file_basename: continue to >>>> breakpoint: \ >>>> compdir_missing__ldir_missing__file_basename >>>> ... >>>> >>>> When trying to set a breakpoint on >>>> compdir_missing__ldir_missing__file_basename, the architecture- >>>> specific >>>> prologue skipper starts at 0x4004c0 and skips past two insns, to >>>> 0x4004c4: >>>> ... >>>> 00000000004004c0 <compdir_missing__ldir_missing__file_basename>: >>>> 4004c0: 55 push %rbp >>>> 4004c1: 48 89 e5 mov %rsp,%rbp >>>> 4004c4: 8b 05 72 1b 20 >>>> 00 mov 0x201b72(%rip),%eax # 60203c <v> >>>> 4004ca: 83 c0 01 add $0x1,%eax >>>> 4004cd: 89 05 69 1b 20 >>>> 00 mov %eax,0x201b69(%rip) # 60203c <v> >>>> 4004d3: 90 nop >>>> 4004d4: 5d pop %rbp >>>> 4004d5: c3 ret >>>> ... >>>> >>>> And because the line table info is rudamentary: >>>> ... >>>> CU: tmp-dw2-dir-file-name.c: >>>> File name Line number Starting >>>> address View Stmt >>>> tmp-dw2-dir-file- >>>> name.c 999 0x4004c0 x >>>> tmp-dw2-dir-file- >>>> name.c 1000 0x4004d6 x >>>> tmp-dw2-dir-file-name.c - 0x4004d6 >>>> ... >>>> the address does not fall at an actual line, so the breakpoint is >>>> shown with >>>> address, both when setting it and hitting it. >>>> >>>> when running the test-case with aarch64-linux, we have similarly: >>>> ... >>>> (gdb) break compdir_missing__ldir_missing__file_basename^M >>>> Breakpoint 2 at 0x400618: file tmp-dw2-dir-file-name.c, line >>>> 999.^M >>>> ... >>>> due to the architecture-specific prologue skipper starting at >>>> 0x400610 and >>>> skipping past two insns, to 0x400618: >>>> ... >>>> 0000000000400610 <compdir_missing__ldir_missing__file_basename>: >>>> 400610: 90000100 adrp x0, 420000 < >>>> __libc_start_main@GLIBC_2.17> >>>> 400614: 9100b000 add x0, x0, #0x2c >>>> 400618: b9400000 ldr w0, [x0] >>>> 40061c: 11000401 add w1, w0, #0x1 >>>> 400620: 90000100 adrp x0, 420000 < >>>> __libc_start_main@GLIBC_2.17> >>>> 400624: 9100b000 add x0, x0, #0x2c >>>> 400628: b9000001 str w1, [x0] >>>> 40062c: d503201f nop >>>> 400630: d65f03c0 ret >>>> ... >>>> >>>> But interestingly, the aarch64 architecture-specific prologue >>>> skipper is >>>> wrong. There is no prologue, and the breakpoint should be set at >>>> 0x400610. >>>> >>>> By using "break *compdir_missing__ldir_missing__file_basename" >>>> we can get the breakpoint set at 0x400610: >>>> ... >>>> (gdb) break *compdir_missing__ldir_missing__file_basename^M >>>> Breakpoint 2 at 0x400610: file tmp-dw2-dir-file-name.c, line >>>> 999.^M >>>> ... >>>> and make the test-case independent of prologue analysis. >>>> >>>> This requires us to update the expected patterns. >>>> >>>> The fix ensures that once the aarch64 architecture-specific >>>> prologue skipper >>>> will be fixed, this test-case won't start failing. >>>> >>>> Tested on x86_64-linux. >>>> >>>> Any comments? >>>> >>>> Thanks, >>>> - Tom >>>> >>>> [gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp >>>> >>>> --- >>>> gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp | 8 ++++---- >>>> gdb/testsuite/lib/gdb.exp | 7 ++++++- >>>> 2 files changed, 10 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>> b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>> index 4d3f767f597..4c4c1ff07af 100644 >>>> --- a/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>> +++ b/gdb/testsuite/gdb.dwarf2/dw2-dir-file-name.exp >>>> @@ -396,20 +396,20 @@ proc test { func compdir filename } { >>>> error "not absolute" >>>> } >>>> >>>> - gdb_breakpoint $func >>>> + gdb_breakpoint *$func >>>> gdb_continue_to_breakpoint $func "$func \\(\\) at .*" >>>> >>>> gdb_test_no_output "set filename-display absolute" >>>> verbose -log "expect: ${absolute}" >>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp >>>> ${absolute}]:999" "absolute" >>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp >>>> ${absolute}]:999" "absolute" >>>> >>>> gdb_test_no_output "set filename-display basename" >>>> verbose -log "expect: [file tail $filename]" >>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp [file >>>> tail $filename]]:999" "basename" >>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp [file >>>> tail $filename]]:999" "basename" >>>> >>>> gdb_test_no_output "set filename-display relative" >>>> verbose -log "expect: $filename" >>>> - gdb_test "frame" " in $func \\(\\) at [string_to_regexp >>>> $filename]:999" "relative" >>>> + gdb_test "frame" "#0 $func \\(\\) at [string_to_regexp >>>> $filename]:999" "relative" >>>> } >>>> } >>>> >>>> diff --git a/gdb/testsuite/lib/gdb.exp >>>> b/gdb/testsuite/lib/gdb.exp >>>> index a8f25b5f0dd..70fc019eeb9 100644 >>>> --- a/gdb/testsuite/lib/gdb.exp >>>> +++ b/gdb/testsuite/lib/gdb.exp >>>> @@ -787,9 +787,14 @@ proc gdb_continue_to_breakpoint {name >>>> {location_pattern .*}} { >>>> global gdb_prompt >>>> set full_name "continue to breakpoint: $name" >>>> >>>> + set re_at_in " (at|in) " <-NEED TO FIX TO ALWAYS GIVE local entry point for POWERPC ?? >>>> + if { [regexp $re_at_in $location_pattern] } { >>>> + set re_at_in " " >>>> + } >>>> + >>>> set kfail_pattern "Process record does not support >>>> instruction 0xfae64 at.*" >>>> gdb_test_multiple "continue" $full_name { >>>> - -re "(?:Breakpoint|Temporary breakpoint) .* (at|in) >>>> $location_pattern\r\n$gdb_prompt $" { >>>> + -re "(?:Breakpoint|Temporary breakpoint) >>>> .*$re_at_in$location_pattern\r\n$gdb_prompt $" { >>>> pass $full_name >>>> } >>>> -re "\[\r\n\]*(?:$kfail_pattern)\[\r\n\]+$gdb_prompt $" >>>> { > ^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2022-09-01 14:40 UTC | newest] Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-08-11 11:58 [PATCH][gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp Tom de Vries 2022-08-12 9:33 ` Luis Machado 2022-08-15 16:01 ` Carl Love 2022-08-15 16:54 ` Carl Love 2022-08-15 19:12 ` will schmidt 2022-08-15 19:31 ` Thiago Jung Bauermann 2022-08-15 21:33 ` will schmidt 2022-08-16 7:43 ` Luis Machado 2022-08-16 16:00 ` will schmidt 2022-08-17 12:01 ` Ulrich Weigand 2022-09-01 14:40 ` Tom de Vries 2022-09-01 14:16 ` Tom de Vries
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